Carbonylative synthesis and functionalization of indoles

• Alex De Salvo,
• Raffaella Mancuso and
• Xiao-Feng Wu

Beilstein J. Org. Chem. 2024, 20, 973–1000, doi:10.3762/bjoc.20.87

• et al. proposed the synthesis of 2-(1H-indol-2-yl)phenyl tosylates via a Pd-catalyzed cycloaminocarbonylation reaction [58]. In this approach Pd(TFA)2/dppp was the catalyst system and able to catalyze the reaction in the best way. Also in this case a base was added to improve the reaction under 10

• functionalization of indoles to 3-substituted indoles Functionalization through direct C–H alkoxycarbonylation The transition-metal-catalyzed carbonylation of aryl halides, triflates, and tosylates with carbon monoxide and an alcohol was first pioneered by Heck and co-workers in 1974 [64][65]. Since then, this

Benzoimidazolium-derived dimeric and hydride n-dopants for organic electron-transport materials: impact of substitution on structures, electrochemistry, and reactivity

• Swagat K. Mohapatra,
• Khaled Al Kurdi,
• Samik Jhulki,
• Georgii Bogdanov,
• John Bacsa,
• Maxwell Conte,
• Tatiana V. Timofeeva,
• Seth R. Marder and
• Stephen Barlow

Beilstein J. Org. Chem. 2023, 19, 1651–1663, doi:10.3762/bjoc.19.121

• iodomethane (or methyl tosylate) to afford the benzimidazolium iodides (or tosylates), 1+I− (or 1+OTs−), which were metathesized to the corresponding hexafluorophosphates, 1+PF6−. Either I− or PF6− salt can then be converted to the corresponding 1H derivative using NaBH4 in MeOH. The PF6− salts are somewhat

Photoredox catalysis harvesting multiple photon or electrochemical energies

• Mattia Lepori,
• Simon Schmid and
• Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

Pyridine C(sp²)–H bond functionalization under transition-metal and rare earth metal catalysis

• Haritha Sindhe,
• Malladi Mounika Reddy,
• Karthikeyan Rajkumar,
• Akshay Kamble,
• Amardeep Singh,
• Anand Kumar and
• Satyasheel Sharma

Beilstein J. Org. Chem. 2023, 19, 820–863, doi:10.3762/bjoc.19.62

• groups used Pd(OAc)2 as catalyst with 1,10-phenanthroline as ligand. The group of Yu used aryl halides 137 as coupling partner, whereas the group of Tan utilized aryl tosylates 142 as coupling partner (Scheme 26). The Yu group also applied the developed protocol for the synthesis of the drug molecule

Investigation of cationic ring-opening polymerization of 2-oxazolines in the “green” solvent dihydrolevoglucosenone

• Solomiia Borova and
• Robert Luxenhofer

Beilstein J. Org. Chem. 2023, 19, 217–230, doi:10.3762/bjoc.19.21

• polymerization (CROP) of the respective 2-substituted 2-oxazoline (Figure 1) initiated with various electrophiles [18][19][20][21]; most commonly alkyl tosylates or triflates are applied [21][22][23][24]. The use of suitable solvents plays a significant role in obtaining well-defined polymers with a narrow molar

• separated and the remaining oil was further dried for 10 h at 1 mbar. A white powder was obtained with a moderate yield of 74% (2.37 g). Results and Discussion Polymerization of 2-methyl-2-oxazoline The CROP of 2-oxazolines is commonly initiated by alkyl tosylates [41][42][43] and alkyl triflates [41][42

Regioselectivity of the S_EAr-based cyclizations and S_EAr-terminated annulations of 3,5-unsubstituted, 4-substituted indoles

• Jonali Das and
• Sajal Kumar Das

Beilstein J. Org. Chem. 2022, 18, 293–302, doi:10.3762/bjoc.18.33

• synthesis of pyrano[2,3-e]indol-3-ols 41 via trifluoroethanol-mediated intramolecular ring-opening cyclization of 4-(2-oxiranylmethoxy)indoles 40 which were prepared by O-alkylation of 4-hydroxyindole 38 using epoxy tosylates 39 as the alkylating agents, followed by (in selected cases) N-tert

Photoredox catalysis in nickel-catalyzed C–H functionalization

• Lusina Mantry,
• Rajaram Maayuri,
• Vikash Kumar and
• Parthasarathy Gandeepan

Beilstein J. Org. Chem. 2021, 17, 2209–2259, doi:10.3762/bjoc.17.143

• (sp3)‒H bonds with aryl tosylates/triflates 11. The relatively less expensive ruthenium photocatalyst Ru(bpy)3Cl2·6H2O was found to be optimal for primary C(sp3)‒H arylations (Scheme 7a), whereas Ir[dF(CF3)ppy]2(dtbbpy)PF6 was the effective photocatalyst for the arylation of secondary C(sp3)‒H bonds

• (Scheme 7b). In a subsequent report, Yu and co-workers also realized the arylation of α-amino C(sp3)‒H bonds with aryl tosylates 11 generated in situ from phenols 12 and p-toluenesulfonyl chloride (TsCl) [59][60]. The combination of visible-light-photoredox catalysis, hydrogen-atom-transfer catalysis, and

• developed due to lower reactivity, poor regioselectivities and the need of noble metal catalysts [50][102][103][104][105][106]. Recently, Yu and co-workers conveniently achieved the direct alkenylation of α-amino C(sp3)–H bonds of amines 1 with alkenyl tosylates 58. The combination of the Ru(bpy)3Cl2·6H2O

Regioselective N-alkylation of the 1H-indazole scaffold; ring substituent and N-alkylating reagent effects on regioisomeric distribution

• Ryan M. Alam and
• John J. Keating

Beilstein J. Org. Chem. 2021, 17, 1939–1951, doi:10.3762/bjoc.17.127

• electrophile under conditions A (Table 6, entry 8) furnished the desired N-1 regioisomer 75 in very good isolated yield (81%). These latter results would suggest that secondary alkyl tosylates are more suitable than their corresponding halide counterparts, for N-1 regioselective alkylation, under these

CF₃-substituted carbocations: underexploited intermediates with great potential in modern synthetic chemistry

• Anthony J. Fernandes,
• Armen Panossian,
• Bastien Michelet,
• Agnès Martin-Mingot,
• Frédéric R. Leroux and
• Sébastien Thibaudeau

Beilstein J. Org. Chem. 2021, 17, 343–378, doi:10.3762/bjoc.17.32

• solvolysis rate for derivatives 13f or 13g and the solvent polarity parameter YOTs [45]. The solvent participation in the solvolysis of these tertiary benzylic tosylates was thus defined as “unimportant” by the authors. Gassman and Harrington successfully measured the solvolysis kinetics of CF3-substituted

• preliminary results, Tidwell et al. envisioned the possibility to study the solvolysis reaction of secondary benzylic sulfonates [48]. In tertiary benzylic sulfonates [39][43], a linear free-energy relationship between the solvolysis rate for the secondary benzylic tosylates 21 (Figure 4) and YOTs was

• nucleophilic and less ionizing solvents, in agreement with an increased electron demand on the aromatic substituent in a poorly ionizing solvent. This also suggests that the positive charge is delocalized to a higher extent on the aromatic substituent for the secondary tosylates than for the tertiary ones

The preparation and properties of 1,1-difluorocyclopropane derivatives

• Kymbat S. Adekenova,
• Peter B. Wyatt and
• Sergazy M. Adekenov

Beilstein J. Org. Chem. 2021, 17, 245–272, doi:10.3762/bjoc.17.25

• bond is opposite to the fluorinated fragment (the distal bond) [2]. The ring-opening reactions of (2,2-difluorocyclopropyl)methyl systems: Dolbier investigated the acetolysis of tosylates 104 and 105 (Scheme 48) [96]. The difference between compounds 104 and 105 is the presence of a methyl substituent

Copper-based fluorinated reagents for the synthesis of CF₂R-containing molecules (R ≠ F)

• Louise Ruyet and
• Tatiana Besset

Beilstein J. Org. Chem. 2020, 16, 1051–1065, doi:10.3762/bjoc.16.92

• halides and tosylates, iodoalkynes and reactive alkyl halides were realized. It was established that CuCF2H readily decompose into 1,1,2,2-tetrafluoroethane and cis-difluoroethylene. From this pioneer work, attention was paid either to the design of new synthetic pathways for the synthesis of a well

Recent advances in Cu-catalyzed C(sp³)–Si and C(sp³)–B bond formation

• Balaram S. Takale,
• Ruchita R. Thakore,
• Elham Etemadi-Davan and
• Bruce H. Lipshutz

Beilstein J. Org. Chem. 2020, 16, 691–737, doi:10.3762/bjoc.16.67

• conditions, a rare cross-coupling takes place (Scheme 62) [115]. The cooperative effect of a catalytic system consisting of Cu/Ni (e.g., Ni(acac)2, CuCl, and PCy3) was also reported by Nakao et al. leading to regio- and stereoselective arylboration of 1-arylalkenes with aryl chlorides or tosylates. The

Thermal stability of N-heterocycle-stabilized iodanes – a systematic investigation

• Andreas Boelke,
• Yulia A. Vlasenko,
• Mekhman S. Yusubov,
• Boris J. Nachtsheim and
• Pavel S. Postnikov

Beilstein J. Org. Chem. 2019, 15, 2311–2318, doi:10.3762/bjoc.15.223

• , (b) triazole 2 and (c) pyrazole 6. Decomposition enthalpy (ΔHdec) scale for pseudocyclic tosylates 1–15 and cyclic iodoso species 16 and 17. Correlation between the relative reactivity for pseudocyclic NHIs based on the reaction time in the oxidation of thioanisole with the corresponding

Recent advances on the transition-metal-catalyzed synthesis of imidazopyridines: an updated coverage

• Gagandeep Kour Reen,
• Ashok Kumar and
• Pratibha Sharma

Beilstein J. Org. Chem. 2019, 15, 1612–1704, doi:10.3762/bjoc.15.165

An improved synthesis of adefovir and related analogues

• David J. Jones,
• Eileen M. O’Leary and
• Timothy P. O’Sullivan

Beilstein J. Org. Chem. 2019, 15, 801–810, doi:10.3762/bjoc.15.77

• the synthesis of acyclic nucleoside phosphonates including mesylates [42], tosylates [16][43][44] and alkyl chlorides [45][46][47][48][49][50][51]. Alkylation reactions conducted with these electrophiles generally require higher temperatures. Furthermore, these reagents typically afford products in

Homo- and hetero-difunctionalized β-cyclodextrins: Short direct synthesis in gram scale and analysis of regiochemistry

• Gábor Benkovics,
• Mihály Bálint,
• Éva Fenyvesi,
• Erzsébet Varga,
• Szabolcs Béni,
• Konstantina Yannakopoulou and
• Milo Malanga

Beilstein J. Org. Chem. 2019, 15, 710–720, doi:10.3762/bjoc.15.66

• optimization this chromatographic method can be applied also for preparative purposes. As a final proof for the side-selectivity of stepwise hetero-difunctionalizations, part of the azido-tosylates prepared in reactions 4–8 were transformed to the diazido-β-CDs (reactions 9–13, Scheme 3). As the reversed-phase

Imide arylation with aryl(TMP)iodonium tosylates

• Souradeep Basu,
• Alexander H. Sandtorv and
• David R. Stuart

Beilstein J. Org. Chem. 2018, 14, 1034–1038, doi:10.3762/bjoc.14.90

• % yield from 1a (Scheme 3). We have previously described the coupling of aryl(TMP)iodonium tosylates with azide nucleophiles [14]. Azide is a notably stronger nucleophile than phthalimide and it is interesting to compare the reaction of these two nucleophiles with 1a under similar conditions (Table 2

Progress in copper-catalyzed trifluoromethylation

• Guan-bao Li,
• Chao Zhang,
• Chun Song and
• Yu-dao Ma

Beilstein J. Org. Chem. 2018, 14, 155–181, doi:10.3762/bjoc.14.11

• explored the trifluoromethylation of primary and secondary alkylboronic acids with the Ruppert–Prakash reagent (TMSCF3) (Scheme 17) [32]. These alkylboronic acids were prepared from the corresponding alkyl halides or tosylates by using their previously developed Cu-catalyzed borylation method [33]. Both

CF₃SO₂X (X = Na, Cl) as reagents for trifluoromethylation, trifluoromethylsulfenyl-, -sulfinyl- and -sulfonylation. Part 1: Use of CF₃SO₂Na

• Hélène Guyon,
• Hélène Chachignon and
• Dominique Cahard

Beilstein J. Org. Chem. 2017, 13, 2764–2799, doi:10.3762/bjoc.13.272

Nucleophilic displacement reactions of 5′-derivatised nucleosides in a vibration ball mill

• Olga Eguaogie,
• Patrick F. Conlon,
• Francesco Ravalico,
• Jamie S. T. Sweet,
• Thomas B. Elder,
• Louis P. Conway,
• Marc E. Lennon,
• David R. W. Hodgson and
• Joseph S. Vyle

Beilstein J. Org. Chem. 2017, 13, 87–92, doi:10.3762/bjoc.13.11

• ′-tosylates in five to 60 minutes. Under these conditions, commonly-encountered nucleoside cyclisation byproducts (especially of purine nucleosides) were not observed. Liquid-assisted grinding of the same 5'-iodide and 5′-tosylate substrates with potassium selenocyanate in the presence of DMF produced the

New syntheses of (±)-tashiromine and (±)-epitashiromine via enaminone intermediates

• Darren L. Riley,
• Joseph P. Michael and
• Charles B. de Koning

Beilstein J. Org. Chem. 2016, 12, 2609–2613, doi:10.3762/bjoc.12.256

• attempt to circumvent the issues associated with the purification of the cyclic enamines, we investigated the conversion of alcohols 8c and 8d into the corresponding tosylates followed by treatment with sodium iodide as an alternative for the cyclisation step. The tosylations afforded 10c and 10d in 19

A procedure for the preparation and isolation of nucleoside-5’-diphosphates

• Heidi J. Korhonen,
• Hannah L. Bolt and
• David R. W. Hodgson

Beilstein J. Org. Chem. 2015, 11, 469–472, doi:10.3762/bjoc.11.52

• ’-tosylates and their 1H and 13C NMR spectra, and 31P and 1H NMR spectra of NDPs. Acknowledgements This work was supported by the Jenny and Antti Wihuri Foundation (H.J.K), Durham University (H.L.B.) and the Royal Society (chromatography system).

Synthesis and chemosensing properties of cinnoline-containing poly(arylene ethynylene)s

• Natalia A. Danilkina,
• Petr S. Vlasov,
• Semen M. Vodianik,
• Andrey A. Kruchinin,
• Yuri G. Vlasov and
• Irina A. Balova

Beilstein J. Org. Chem. 2015, 11, 373–384, doi:10.3762/bjoc.11.43

• - and hetaryliodides, -bromides -tosylates and -triflates [47][48][49][50], there are only a few examples where polycondensation was carried out under these conditions [58][59][60]. In our case this approach seemed to be more convenient than the common Sonogashira coupling, because it allows TMS

Matsuda–Heck reaction with arenediazonium tosylates in water

• Ksenia V. Kutonova,
• Marina E. Trusova,
• Andrey V. Stankevich,
• Pavel S. Postnikov and
• Victor D. Filimonov

Beilstein J. Org. Chem. 2015, 11, 358–362, doi:10.3762/bjoc.11.41

• Chemistry of New Materials NAS Belarus, 220141, Minsk, Belarus Department of General and Inorganic Chemistry, National Research Tomsk Polytechnic University, 634050 Tomsk, Russia 10.3762/bjoc.11.41 Abstract An environmentally friendly Matsuda–Heck reaction with arenediazonium tosylates has been developed

• were rather less reactive under these conditions, and products were obtained with low to modest yields [9]. Previously, we described a novel type of diazonium salt – arenediazonium tosylates (ADT), which differ from arenediazonium tetrafluoroborates in their higher stability at a dry state and their

• in water at 75 °C in a microwave reactor was selected as the best reaction conditions. To evaluate the scope of this reaction, a variety of arenediazonium tosylates 2a–i and a range of alkenes 1a–c were used (Scheme 2, Table 2). Our method displays a general applicability. The arylation of methyl

Superoxide chemistry revisited: synthesis of tetrachloro-substituted methylenenortricyclenes

• Basavaraj M. Budanur and
• Faiz Ahmed Khan

Beilstein J. Org. Chem. 2014, 10, 2531–2538, doi:10.3762/bjoc.10.264

• ][11][12][13][14][15], hydrolysis and substitution reactions [16][17][18]. Filippo and co-workers [19][20][21][22] have extensively studied the substitution reactions of alkyl halides and tosylates; oxidative cleavage reactions and hydrolysis of esters. Frimer and co-workers [23][24] have studied its